This invention relates to protective helmets as used in the sports of vehicle racing, where high speeds result in damaging wind velocities. That is, high wind velocites are encountered that are detremental to the human face and a hinderance to eyesight. Accordingly, protective helmets are worn by the sportsman, characterized by a viewing window closed by a transparent shield that is partially and/or completely removable for access and ventilation. Race conditions vary from clear to inclement, with regard to temperature and debris, including wetness, carried by the wind. Therefore, ventilation may or may not be required dependant upon outside temperature, wind velocity, and the general condition of the atmosphere. For example, it may be desired that the shield be sealed at its periphery to the helmet window opening, or it may be desired to open the shield partially in order to prevent "fogging" as a result of the person's breathing. Or it may be desired to fully open the shield for access to the person's face for eye, nose and throat attention, all without removing the helmet from the person's head.
In view of the foregoing, there is a need for face shield control on helmets of the type under consideration, all of which has to do with the manner by which said shield is attached to the helmet, it being a general object of this invention to provide a positive control system that locks the shield tightly to the helmet window throughout the periphery of the seal.
It is also an object of this invention to provide a control system that releases the periphery of the shield from the seal for slight ventilation, and also to maintain substantially a half volume condition of air flow through the window.
And it is still another object of this invention to provide a control that establishes and maintains a fully open condition of the shield whereby the helmet window is unobstructed.
The shield as disclosed herein is secured in each of the aforementioned conditions by detent means incorporated in said control. In practice, the movement of the shield clears the normal external features of such a helmet, and is adapted to the helmet with a threaded anchor or insert. Control is by means of a single member in the form of a flat plate having a plurality of slots directing motion of and positioning the shield. In practice, the shield has a temple portion through which an opening receives and positions a spring member, and over which there is an operating member attached to the shield for its manipulated poistioning as may be required.
As shown and herein described, there are four basic postions and/or conditions of the shield: 1) a closed sealed condition excluding outside access and precluding entry of air into the helmet; 2) a forwardly shifted condition for slight ventilation to prevent fogging; 3) and a partially lifted condition for ventilation and free breathing; and 4) a lifted open condition for full access.
In carrying out this invetnion, the control features are applied to the left temple portion side of the helmet. However, it is to be understood that this face shield control can be applied to either or both sides of the helmet, a feature being its adequacy applied to one side only.